The invention relates generally to the field of accessories for commercial trucks, and specifically to devices that reduce drag on trucks, thereby improving trucks' energy efficiency and reducing fuel cost. Numerous air flow conduits and foils are taught in the prior art to reduce drag and increase fuel economy on trucks, trailers, cargo containers, railway cars, and the like. These devices, however, typically focus on distributing air flow from the top, bottom, front, or sides of the vehicle to the rear. No known device distributes air in an outward direction near the rear.